bug#46722: test-map-into fails

[Glenn Morris]

Package: emacs
Version: 28.0.50

Something between 8d5dfaf and efe42c2 (inclusive) causes test-map-into
to reliably fail on hydra.nixos.org. We can't be more specific since
intermediate revisions don't build. So far I could not reproduce the issue.

Ref eg https://hydra.nixos.org/build/137474120

(cl-no-applicable-method map-into ((a . 1) (b . 2)) (hash-table :test equal))